Eh.. you could use a custom installer that supports esd files, but definitely not the Windows Setup program.
But I found tons of ISO with Windows 7 with install.esd. Like this one Windows 7 Sp1 Ultimate 16in1 [x86 x64] OEM ESD en-US Oct 2014 by Generation2-=TEAM OS=-{HKRG} I know it's warez but I've downloaded it to try to understand how it works but I didn't understand.
Doesn't work. I've got this: they use the root files and the boot and the efi folders from Windows 8 but for sure they have a modified boot.wim a mix from Windows 7 and Windows 8 but their version doesn't work for my iso.
I mounted to compare boot.wim index 1 and index 2 at the same time of win7 msdn, win8 msdn and the mixed one with GImageX v2 and used Beyond Compare 4 but I didn't get where are the significative differences.
A workaround I've been using to circumvent that incompatibility is to use Windows 8.1 setup files. Just put Win7 install.esd and delete/overwrite any install.wim or install.esd found in Win8.1 iso. I know is not cute but it's the easiest way, at least for me.
I found it! Just need to mount boot.wim index 2 from Windows 7 and copy ARUNIMG.dll and spwizimg.dll from sources folder and replace the ones into boot.wim index 2 of Windows 8 in sources and into Windows\WinSxS\x86_microsoft-windows-i..dia-branding-client_31bf3856ad364e35_6.3.9600.16384_none_401c2bae8f94fbe2. Commit changes and it's done!
Thanks a lot for this trick of yours, lol I guess it's yours Two questions arise: 1. Did you find any glitch by doing this? 2. In case of an upgrade (I've just tested on clean installs) does Win8.1 setup files are still functional? For instance upgrading a pc from Win7 to Win8.1
You may just be able to replace the images in spwizimg. You can try with Windows Download integrator 3.5
I didn't have the time today. Today I just found the answer I was looking for. Next days I will go through some full testing and I will report here. At the end the solution it's truly simple but not that easy to find!